Phosphate will perk up grass
AUTUMN phosphate fertiliser applications to low fertility soils will maximise grass growth both now and next spring, says William Murphy of the Johnstown Castle Research Centre, Wexford, Ireland.
In his studies, where phosphate and potash were applied to low and medium fertility soils, autumn applications gave a 15% increase in the grass available for the first spring grazing compared with spring applications.
Mike Dewhurst of Fieldfare Associates advises low fertility fields (below soil index 2) ear-marked for silaging next year be dressed with manure or a fertiliser such as 0:15:30 applied this autumn or winter.
High levels of phosphate and potash are removed in cut grass, he warns, with 2kg (4 units) of phosphate and 6kg (12 units) of potash removed per tonne of 20% dry matter silage taken.
Medium fertility grazing fields require small amounts of phosphate and potash applied mid-season. "Where phosphate is low up to 60kg/ha can be applied between September and March," he says. *